The Anthropocene is proposed as a new interval of geological time in which human influence on Earth and its geological record dominates over natural processes. A major challenge in demarcating the Anthropocene is that the balance between human-influenced and natural processes varies over spatial and temporal scales owing to the inherent variability of both human activities (as associated with culture and modes of development) and natural drivers (e.g. tectonic activity and sea level variation). Against this backdrop, we consider how geomorphology might contribute towards the Anthropocene debate by focusing on human impact on aeolian, fluvial, cryospheric and coastal process domains, and how evidence of this impact is preserved in landforms and sedimentary records. We also consider the evidence for an explicitly anthropogenic geomorphology that includes artificial slopes and other human-created landforms. This provides the basis for discussing the theoretical and practical contributions that geomorphology can make to defining an Anthropocene stratigraphy. It is clear that the relevance of the Anthropocene concept varies considerably amongst different branches of geomorphology, depending on the history of human actions in different process domains. For example, evidence of human dominance is more widespread in fluvial and coastal records than in aeolian and cryospheric records, so geomorphologically the Anthropocene would inevitably comprise a highly diachronous lower boundary. Even to identify this lower boundary, research would need to focus on the disambiguation of human effects on geomorphological and sedimentological signatures. This would require robust data, derived from a combination of modelling and new empirical work rather than an arbitrary ?war of possible boundaries' associated with convenient, but disputed, ?golden? spikes. Rather than being drawn into stratigraphical debates, the primary concern of geomorphology should be with the investigation of processes and landform development, so providing the underpinning science for the study of this time of critical geological transition. Copyright ? 2016 John Wiley & Sons, Ltd.authorsversionPeer reviewe
This manuscript reviews the progresses made in the understanding of the dynamic interactions between coastal storms and salt marshes, including the dissipation of extreme water levels and wind waves across marsh surfaces, the geomorphic impact of storms on salt marshes, the preservation of hurricanes signals and deposits into the sedimentary records, and the importance of storms for the long term survival of salt marshes to sea level rise. A review of weaknesses, and strengths of coastal defences incorporating the use of salt marshes including natural, and hybrid infrastructures in comparison to standard built solutions is then presented. Salt marshes are effective in dissipating wave energy, and storm surges, especially when the marsh is highly elevated, and continuous. This buffering action reduces for storms lasting more than one day. Storm surge attenuation rates range from 1.7 to 25 cm/km depending on marsh and storms characteristics. In terms of vegetation properties, the more flexible stems tend to flatten during powerful storms, and to dissipate less energy but they are also more resilient to structural damage, and their flattening helps to protect the marsh surface from erosion, while stiff plants tend to break, and could increase the turbulence level and the scour. From a morphological point of view, salt marshes are generally able to withstand violent storms without collapsing, and violent storms are responsible for only a small portion of the long term marsh erosion. Our considerations highlight the necessity to focus on the indirect long term impact that large storms exerts on the whole marsh complex rather than on sole after-storm periods. The morphological consequences of storms, even if not dramatic, might in fact influence the response of the system to normal weather conditions during following inter-storm periods. For instance, storms can cause tidal flats deepening which in turn promotes wave energy propagation, and exerts a long term detrimental effect for marsh boundaries even during calm weather. On the other hand, when a violent storm causes substantial erosion but sediments are redistributed across nearby areas, the long term impact might not be as severe as if sediments were permanently lost from the system, and the salt marsh could easily recover to the initial state.
Introduction. Let / = X)n>i a n(f)Q n € Sko (To{N)) be a normalized newform of even weight fco > 2. Let F be the number field generated by the coefficients of / and p a prime of F lying above a rational prime p. There is a two-dimensional representation V(f) of GQ = Gal (Q/Q) over Fp associated to /, characterized by the conditions It (FWgeomW/)) =<*/(/)det(FV(^) geom |y(/)) = ^-1 for all primes £ { piV. The Tate twist Vk 0 = V(f)(ko/2) is self dual: there is a skew-symmetric bilinear formThe complex L-function L 00 (f, s) = ^2n>1 cin(/)^~s satisfies the functional equation Aoo(/, s) := ( -J r(s)L 00 (/, s) = Woo(/)Aoo(/, fco -5), where w 00 (f) = ±1 = (-l) eo0 for eoo = 0 or 1. Bloch and Kato [BI-Ka] defined a generalized "Selmer group" Hj(Q,V ko ) C i? 1 (Q, Vk 0 ) and conjectured that ord^/aLooCf,*) = dim Fp H}(Q, Vi 0 ).We are interested in a (mod 2) version of this conjecture:The Parity Conjecture for ranks of Selmer groups ord a=ibo/ 2Loo(/,s) = dim Fp if}(Q,^0) (mod 2).Assume that p > 3 and that / is ordinary at p, i.e. that ap(f) 6 Fp is a p-adic unit. According to Hida's theory, there is a p-adic family of ordinary modular forms of varying weights containing / (we ignore the phenomenon of "p-stabilization" in this Introduction). In concrete terms, this means that there is an integer c > 0 such that for every integer k > 2 satisfying k = ko (mod (p -l)p c ), there is an ordinary newform fk of weight k on ro(iV) such that /fc 0 = / and . k = k' (mod (p -l)p n+c ) implies /* = /*' (modp"). LetAT, k = 2, a p (f) = 1, f 1 ifp\ \ 0 other otherwise.
The version presented here may differ from the published version. If citing, you are advised to consult the published version for pagination, volume/issue and date of publication 1 Exploring the socio-cultural contexts of fishers and fishing: developing the concept of the 'good fisher'
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